32 lines
1.1 KiB
Agda
32 lines
1.1 KiB
Agda
{- This says that ⊥ is the proposition where there are no proofs of it. -}
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{-
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Given two propositions P and Q, we can form a new proposition 'P implies Q'
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written P → Q
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To introduce a proof of P → Q we assume a proof x of P and give a proof y of Q
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Here is an example demonstrating → in action
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-}
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-- TrueToTrue : ⊤ → ⊤
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-- TrueToTrue = ?
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{-
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* press C-c C-l (this means Ctrl-c Ctrl-l) to load the document,
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and now you can fill the holes
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* press C-c C-r and agda will try to help you,
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* you should see λ x → { }
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* navigate to the hole { } using C-c C-f (forward) or C-c C-b (backward)
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* to check what agda wants in the hole use C-c C-,
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* the Goal area should look like
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Goal: ⊤
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————————————————————————————————————————————————————————————
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x : ⊤
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* this means you have a proof x : ⊤ and you need to give a proof of ⊤
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* you can now give it a proof of ⊤ and press C-c C-SPC to fill the hole
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There is more than one proof (see answers) - are they the same?
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-}
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-- solutions:
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